Murder Row Dungeon
This has now been hotfixed
The 2nd boss of Murder Row is Zaen Bladesorrow, who throws barrels into the arena, some of which are Fel-Infused Freight. These Fel-Infused Freights are supposed to do AoE damage to the group and players are supposed to destroy them with abilities to prevent the AoE damage from stacking.
As the season has progressed, players have discovered that damage from Fel-Infused Freights (aka the Green Barrels) is actually "fake damage"; it only looks real because your health bar drops and scrolling battle text indicates you're taking damage. But you can go down to 1 HP and keep taking damage from the green barrels and you won't actually die because none of it is real.
In reality, the UI on this encounter doesn't show you the truth. The only real source of AoE damage for non-tanks is Killing Spree and apart from this, your health is likely topped off behind the scenes, despite what your health bar shows you. Your health bar updates to the true value whenever you take a real point of damage, which includes the boss melees for the Tank. For the rest of the party, your health will only update on the big AoE or if you use a self-damaging ability such as Burning Rush for Warlocks. This is why you'll see everyone's health bar jump up to near full health when the AoE starts.
This "fake damage" event can be seen in logs as well. The damage taken will be shown, but you can see that the Health Bars don't actually move.
This is the reason why Mistweaver spells don't work as expected or why you might not be able to Health Pot or Healthstone on this boss. You aren't seeing your party's actual health and Smart Healing effects are working off the correct numbers. You can't Health Potion at full health!
If you're going for time on this boss, your healer really only needs to heal Killing Spree and then can avoid healing until the next one. The raid frames will show non-tanks at 1 HP, but they're actually at full health!
